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Re: The lost formula - Printable Version +- HP Forums (https://archived.hpcalc.org/museumforum) +-- Forum: HP Museum Forums (https://archived.hpcalc.org/museumforum/forum-1.html) +--- Forum: Old HP Forum Archives (https://archived.hpcalc.org/museumforum/forum-2.html) +--- Thread: Re: The lost formula (/thread-177165.html) |
Re: The lost formula - John B. Smitherman - 01-17-2011 We don't know what we don't know.
John
Re: The lost formula - Martin Pinckney - 01-17-2011 If anyone understands the meaning of this thread, I would like to know.
Re: The lost formula - Norman Dziedzic - 01-17-2011 Seems to me like just a question of curve fitting. A thermistor is an electronic device whose resistance changes with temperature in a predictable, albeit nonlinear, way. See:http://www.vishay.com/doc?29053
I'm guessing the OP used to have a simple equation to approximate a particular thermistor response at one time and lost it.
Re: The lost formula - Martin Pinckney - 01-17-2011 Thanks for responding, Norman. Quote: That much I got.
Quote:The rest not so much. Re: The lost formula - lost in translation - Norman Dziedzic - 01-17-2011 I think I had my high pass filter on and didn't absorb that part of the thread ;-/
Re: The lost formula - Walter B - 01-17-2011 Martin,
let me explain. As far as I understood the OP, he
If that behaviour is of practical relevance, it was solved in the time between - or it can be modeled easily by some brute force fitting algorithm using the tools available today, which where beyond imagination decades ago. So the OP's problem is most probably solved now either way by the advancement of science ... dona eo pacem! HTH. I'm most willing, however, to delete my two postings in this thread if they will cause any trouble whatsoever ...
Re: The lost formula - Martin Pinckney - 01-17-2011 Walter, I think I've got it now. Thanks for your help.
No need to delete anything.
Re: The lost formula - designnut - 01-18-2011 I think I probably started adding 273 to the C temperature and found that was not quite the right slope and adjusted from there. I'll give it a try through programming and see what happens. I know it was dirt simple, probably a temp add-on and a normalizing factor to suit the particular resistance thermistor. Sam
Re: The lost formula - Pal G. - 01-18-2011 Quote:
42.
Re: The lost formula - Martin Pinckney - 01-18-2011 Now that explains it!
Re: The lost formula - Walter B - 01-18-2011 Don't lose your towel, ask Douglas Adams instead ;)
Re: The lost formula - Dan W - 01-18-2011 When I first discovered WolframAlpha, I had to ask it the question of life, the universe, and everything.
It came up with the correct answer. ;)
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